Microwave-Assisted Convenient Synthesis of<i>α</i>,<i>β</i>-Unsaturated Esters and Ketones<i>via</i>Aldol-Adduct Elimination
作者:Pathi Suman、Rayala Nageswara Rao、Bhimapaka China Raju
DOI:10.1002/hlca.201200526
日期:2013.8
Various fluorinated 3‐oxo ester/1,3‐diketones were reacted with carbonyl compounds, in presence of piperidine and under microwave irradiation, to afford (E)‐α,β‐unsaturated esters and ketones in good yields. The systematic study reveals that the reaction proceeded through the formation of aldol adduct. The method provides a new and simple way for C,C bond formations.
Stereoselective epoxidation of electron poor dienes using poly(L-leucine)
作者:Joanne V. Allen、Michael W. Cappi、Pierre D. Kary、Stanley M. Roberts、Natalie M. Williamson、L. Eduardo Wu
DOI:10.1039/a706238i
日期:——
Poly(L-leucine) catalysed oxidation of dienes 2, 3, 10, 16 and 18 and the triene 17 furnishes the corresponding epoxides 4, 5, 11, 19, 21 and 20 respectively in good to excellent yield and in states of high optical purity. Some regioselective reactions of the saturated epoxy ketones 5 and 11 are described.
A Convenient Regiospecific Synthesis of New Conjugated Tetrazole Derivatives via the Reaction of Dienones with the Tetrachlorosilane-Sodium Azide Reagent and their NMR Structural Assignment
作者:Tarek A. Salama、Abdel-Aziz S. El-Ahl、Abdel-Galil M. Khalil、Margret M. Girges、Bernd Lackner、Christian Steindl、Saad S. Elmorsy
DOI:10.1007/s00706-003-0045-x
日期:2003.9.1
facile one step reaction of dienones with a combination of tetrachlorosilane and sodium azide in acetonitrile under mild conditions. A complete structure assignment of three representative examples of the tetrazoles was achieved by advanced 2D NMR measurements including COSY, TOCSY, HSQC, HMBC, N O ESY, and R O ESY experiments.
几种新的1-芳基- ,芳烷基- ,和杂芳基-5-(4-苯-1,3-二烯基)四唑衍生物和稠四唑衍生物是有效地和区域专一性几乎定量产率制备 经由 二烯酮与一个浅显一步反应在温和的条件下将四氯硅烷和叠氮化钠在乙腈中混合使用。的四唑的三种具有代表性的实施例的完整结构分配通过先进的2D NMR测量包括COSY,TOCSY,HSQC,HMBC,N实现 Ó ESY和R ö ESY实验。
METHOD OF ENANTIOSELECTIVE ADDITION TO ENONES
申请人:UANG Biing-Jiun
公开号:US20110282101A1
公开(公告)日:2011-11-17
The present invention relates to a method of enantioselective addition to enones, including: reacting R
3
(CH
2
)
p
CH═CR
5
C(═O)Y(CH
2
)
q
R
4
with R
6
ZnR
7
in the presence of a compound represented by the following formula (I) and a transition metal catalyst,
in which Y, p, q, R
1
, R
2
, R
3
, R
4
, R
5
, R
6
and R
7
are defined the same as the specification. Accordingly, the present invention can perform asymmetric conjugate addition in high yields and enantioselectivity.
A highly regioselective and enantioselective copper-catalyzed 1,4-conjugate addition of Grignard reagents to linear α,β,γ,δ-unsaturated ketones was developed. The 1,4-addition products were obtained regioselectively in high yields with up to 98% ee.